Respiroscope



NOV. 25, I w; HULL RESPIROSCOPE Filed Sept. 15, 1946 2 Sheets-Sheet 1Ill/ 1 1 a N 0 & 0L V 6 m n 0 N N B H 0 T H m w v. y B

W. E. HULL RESPIROSCOPE Nov. 25, 1947.

I .2 Sheets-Sheet 2 Filed Sept. 15, 1946 l N VEN TOR.

M U E 0 M m w m arms/vans Patented Nov. 25, 1947 RESPIROSCOPE Wayland E.Hull, Dayton, Ohio Application September 13, 1946, Serial No. 696,968

8 Claims.

(Granted under the act The invention described herein may bemanufactured and used by or for the Government for governmental purposeswithout payment to me of any royalty thereon.

This invention relates to a device for continuous observation and rapidestimation of respiratory flow patterns and finds particular utility inobserving respiratory phenomena occurring during surgery, clinicalstudies, and general diagnosis.

One of the essential objects of this invention is to provide a devicefor rapid and continuous observation of respiratory flow patterns,whereby to estimate rapidly the rate of respiration, the depth ofrespiration, and the character of the respiratory flow pattern.

Another object of this invention is to provide a novel and accuratedevice for observing and estimating the respiratory flow pattern, andwhereby such observation and estimation can be made rapidly andsubstantially instantaneously.

Another object of this invention is to provide such a device which iscompact and easy to operate and is also very accurate in observation.

Another object of this invention is to provide such a device whichis ofgreat simplicity of construction, this being preferably accomplished byutilizing purely mechanical-optical means.

These and various other objects and advantages are attained with thisinvention as will become apparent from the following description, takenin connection with the accompanying drawings wherein this invention isshown in its preferred form, it being evident that other arrangementsand forms of construction may be resorted to in carrying out the objectsand purposes of this invention.

In the drawings:

Fig. 1 is an end elevational view of the invention.

Fig. 2 is a longitudinal vertical sectional view, taken substantially online 2-2 of Fig, 1, showing the invention in a preferred form.

Fig. 3 is a partial sectional view thereof, taken substantially alongline 3-3 of Fig. 2, and showing a double set of manometers anddifferential pressure devices.

Fig. 4 is a vertical eter.

Fig. 5 is a sectional detail view, taken on line 5-5 of Fig. 4 andshowing the tiltable. mirror and its supporting bearing.

This device comprises a viewing screen H, which is preferablyfluorescent, and it may be constructed of plastic of optical clarityprovided sectional view of the manomamended April 30, 1928;

of March 3, 1883, as 370 0. G. 757) with a fluorescent salt suspended inthe solvent for the plastic. This fluorescent screen is movable and isherein shown cylindrical and rotary, being supported by and dependingfrom a circular plate or disc l2 which is splined on and is rotated by ashaft [3 supported rotatively in a bracket l4 mounted in a frame orhousing l5. Said shaft is splined to and is driven by a gear l6 actuatedby a pinion l1 secured on and driven by the shaft l8 of a motor l9mounted on said frame l5.

An opticaldifierential manometer 2| (see Figs. 2, 4 and 5) is utilizedherein for indicating respiratory flow rates (or other fluid flowrates). It comprises an air-tight housing 22 having a wafer membrane ordiaphragm 23 mounted therein by a tubular post 24. The interior of thediaphragm 23 and of the hollow post 24 are in open communication with achannel 25 provided in a wall of said housing 22. A deflecting member 26is provided in said housing, being shown as a small mirror carried in aframe 21 and is therewith mounted tiltably by jewelled bearing means 28in a yoke 29 mounted on an apertured disc 30 ex tending across thehousing 22. A link 3i extends through the aperture in disc 36, ispivotally connected with the lower part 21 of said frame 2i, and throughpivoting means 32 with the forwardly expansible front wall 33 of saiddiaphragm 23, so as to tilt the mirror 26 on its bearing means 28 whensaid front wall 33 is moved due to expansion or contraction of saiddiaphragm. A window opening 35 at one end of the housing 22 is coveredby a transparent member 36 secured by a gasket 31, a spacer 38, and acap 39, to seal the opening air-tight but allowing passage of light raystherethrough.

Projecting means is provided herein. which functions in cooperation withsaid deflecting member 26, and it comprises a source of light 40, suchas an electric bulb, supported by bracket or frame means 4| mounted onthe frame l5. A lens system is interposed between said light 46 and themirror 26 and includes a convex lens 4'2 mounted in said means 4| and aconvex lens 43 mounted on a post 44 secured on the frame l5. Theselenses and this light are installed so as to produce a beam of lightcentrally on the mirror 26 which is thereby reflected and caused to fallas a concentrated and intense light spot of small diameter onto thefluorescent cylindrical screen ll, near the central part between theupper and the lower edge of said cylindrical screen.

A differential pressure device is provided which comprises a casing 45having a porous cross-wall or a plate 46 therein extending centrallytherethrough and being of porous or perforated ceramic, or metal so asto divide the casing 45 into two chambers 47 and 48 on the oppositesides of said wall. This will establish a difference in pressure in saidchambers 41 and 48 through pressure drop due to the resistance oiferedby said porous cross-wall 46 to the gas stream passing through thisdevice. Said chamber 47 has a branch or spout 49 thereon with its endopen during air breathing; and said chamber 48 has. a spout 55 thereonadapted for attachment'to the hose of a gas mask, as indicated in thedrawings. A pipe or conduit connects said chamber 41 with said channel25 in the manometer housing 22 and thus places the interiors of thediaphragm 23 and this chamber 4! in communication; while a pipe orconduit 52 likewise connects chamber 48 with the manometer housing 22 toplace their interiors in communication.

The pressure drop effected by the porous wall 46 is substantially of themagnitude of 0 to 1, inch of water for flow rates of Oto 150 liters ofgas per minute, and is proportional to the velocity of the gas flowingthrough the casing 45 into or out of the respiratory maskused herewith.Thus, the instantaneous gas velocities are exhibited as mirrordeflections on the moving screen by this device. i

To use this device during inhalation of any particular gas, theinspiration spout 49 is not left open to the air but is connected withthe tank or container that has the selected gas therein.

This device includes a viewing part or means 53 located and arranged sothat a person can thereby see the essential ray-bearing part or area ofthe screen I and can thereby continuously observe the respiratory flowpattern formed on this rotating fluorescent screen; and to facilitatethis, a viewing scope 54 is preferably provided on this part 53, beingshown as projecting from frame I5.

Although this invention would function effectively with one suchmanometer 2| and one pressure device 45, yet, during inspiration andexpiration, breathing difficulties may finally result. Therefore, asindicated in Fig. 3,1;WO independent optical manometers with two suchpressure de-' vices are preferably used with this invention, and theyare mounted beside each other in the frame l5, one manometer 2| and onedevice 45 being utilized for forming the flow pattern of the'inspiration and the other for forming such pattern of the expiration onscreen The'inspiration pattern is herewith preferably formed as a curveabove the middle or zero line on the screen, and the expiration patternis formed on the screen. Two sets of lenses and lights may be usedherewith, as indicated in Fig. 1, for casting sharp beams on the twomirrors; or additional light deflecting members may be associatedinstead with the one light 48 and its frame means 4| to produce suchdesired effect.

As indicated in Fig. 2, a gas mask 55 is used with this device; and thismask, as illustrated in Fig. 3, is provided with two branches 56 and 56'for connection with the two spouts 59 of the two manometers preferablybeing used herein. A check valve 58 is provided in branch 56 toiadapt itfor inspiration, and a check valve 58' is included in branch 56 forexpiration, bythe u'se of this mask and. device. I

By the use of this device, withthe disclosed twobranch formof gasmask'att'ached to the device, during inspiration the manometer wall 46of the inspiration means 45, on

below such line.

the left-hand side in Fig. 3, restrains the inflow of air or gas throughits spout 49, and the pressure in chamber 41 becomes greater than thepressure in chamber 48 wherein the air has been rarified by theinspiration; consequently, through action of pipe 5|, the pressure inthe interior chamber of diaphragm 23, connected through pipe 5|, becomesgreater than the pressure within the. manometer housing 22, connectedthrough pipe 52 to chamber 48. The diaphragm thereby expands and causesits wall 33 to push link 3| so as to move the attached lower part ofmirror 26 away from the diaphragm.

This will tilt the mirror 26 on its bearings 28, so

asto deflect the light spot further upwardly on the rotating screenabove the base or central line thereon, thereby energizing thefluorescent material and causing it to emit light where the spot strikesthe same. Thus, as the screen rotates, the upward and downward orsubstantially vertical movement of the light spot forms a curve on therotating screen which represents the sum of theinstantaneousinspirational flow rate. Similarly, during expiration thewall 46 of'theexpiration casing 45, at the right-hand side in Fig. 3, retards theoutflow of air or gas, so that the pressure becomes higher in itschamber48 than in chamber 47, and consequently, the pressure within housing 22becomes greater than that within diaphragm 23, thereby'pulling link 3|,and the lower part of mirror 26 toward the diaphragm so as to deflectthe light spot lower on the screen, below the middle or base pressureline thereon, thus showing the expirational flow rate.

The luminous curve hereby formedon said screen travels to the viewingscope. 54 and there can be continuouslyobserved-and-substan-a tiallyinstantaneously estimated. 'The fluorescent screen herein is preferablyrotated at about" one revolution per minute. Thus, by using a type offluorescent material in which the image persists for 10 to 30 seconds,the curves formed. dur.-

ing one respiration. cycle traveling a partial rotationbeyondthe'iviewable area, and that viewed area of the screenisthereafter again ready for further exictation, before making a completerevolution.

The pair of manometers 2| mirrors 26 are slightly tilted ward the screenand viewing scope, so as to reflect the light rays coming from the lenssystem closely together on the screen one above and the other below themiddle line thereon. These light beams are adjusted tofall to the leftor to the right of the center of the viewable area of-the screen orfield of vision as seen 'throu gh'the viewing scope, and the directionof rotation of the screen is then such that the patterns formed byrespiration are carried into and across the field of vision. Therefore,with this rotary fluorescent screen, elimination of the impingement oflight shafts or the movement of light spots within said field of vision,and only the complete patterns arevisible to the observer on this formand type of screen.

Calibration of will disappear after with their pair or the respiroscopeis: accom- -plished by forcing known velocities of gas through thedifferential for inspiration and for expiration. Knowing thetimeinvolved for one respiration and" the maximum of velocity or theestimation can be made of the total. volume, or the amount ofgas-breathed,sincef the respiratory pattern is normally a smooth andnearly sinusoidal curve.

and" converged toconfusion is lessened by pressure device 45, both gasflow," a rapid 7 It will be apparent from the above disclosure that withthe use of this device, each respiratorypattern maybe immediatelyobserved, and estimations rapidly made of the respiratory rate(respirations per minute), since normally respiration is uniformlycyclical, and if the time involved in one respiration is known, thetotal number of respirations which may occur in one minute is easily andvery rapidly estimated. It is furthermore apparent that this device, forrapidly observing and relatively accurately measuring the respiratoryflow pattern, may be used to great advantage in research and clinicalmedicine, where such means of observing the respiratory patternimmediately is of considerable importance.

I claim:

1. A device for continuous observation of a respiratory flow pattern,said device comprising a rotary screen, viewing means for observing saidscreen, means for producing a light ray, a manometer provided with meansfor deflecting the light ray onto said screen, and a differentialpressure device arranged for connection with a gas mask to be therewithactuated by respiration of a person to operate said manometer and thedeflecting means and vary the position of impingement of the rays ontosaid screen, whereby the respiratory flow pattern of the person will betranslated into a moving light ray on the rotating screen.

2. A device for continuous observation of a respiratory flow pattern,said device comprising a rotary fluorescent screen, a viewing scope forobserving said screen, a projecting apparatus for producing a light ray,means for deflecting the light ray onto said screen, means actuated byfluid pressure for moving said deflecting,

means, and a differential pressure device arranged for connection with agas mask to be therewith actuated by respiration of a person to operatesaid fluid pressure actuated means and thereby vary the position ofimpingement of the rays onto said screen, whereby the respiratory flowpattern of the person will be translated into a moving light ray whichtraces a curve on the rotating screen.

3. A device for observation of a respiratory flow pattern, said devicecomprising a rotary fluorescent screen, a viewing scope for observingthe screen, a projecting apparatus including a reflecting member forproducing a light ray on said screen, an expansible member and meansoperatively connecting it with said reflecting member, and adifierential pressure device including a part open to the atmosphere anda part arranged and constructed for connection with a gas mask andoperable by the respiration of the person wearing the mask for actuatingthe expansible member to tilt said deflecting member and move theposition of light on said screen, whereby the respiratory flow patternof the person will be translated into a moving light ray which traces acurve on the rotating screen.

4. A device for continuous observation of a respiratory flow pattern,said device comprising a rotatably mounted fluorescent screen and meansfor rotating the screen, viewing means for observing a part of saidscreen, a projecting apparatus including lighting means and a lenssystem and deflecting means arranged for causing a beam of light toimpinge as an intense spot of light of small diameter onto the screenand to the entrance side of the visible parts of said screen, pressureactuated means to operate said deflecting means, and

a differential pressure device arranged and constructed for connectionwith a gas mask and thus operable by respiration of a person to actuatesaid pressure actuated means and deflecting means and thereby move theposition of said light spot on the screen at an angle to the movement ofthe screen, whereby the respiratory flow pattern of the person will betranslated into a moving light ray which traces a curve on the rotatingscreen continuously observable through said scope.

5. A device for continuous observation of a respiratory flow pattern,said device comprising a cylindrical fluorescent screen and means torotate the screen on its central axis, viewing means positioned tofacilitate observing said screen, a projecting apparatus including areflecting member for producing a light ray on said screen, and meansincluding a fluid pressure sensitive element and a fluid carryingconduit connected to said element for actuating said reflecting memberin response to the respiration of a person breathinginto said conduit tovary the position of the light ray on the screen, whereby therespiratory pattern of the person will be translated into a moving lightray capable of tracing a curve on said rotating screen.

6. A device Or continuous observation of a respiratory flow pattern,said device comprising a casing containing a translucent cylindricalfluorescent screen and means to rotate the screen on its central axis, aviewing scope provided on said casing for observing an exterior part ofsaid screen, a projecting apparatus including a member for reflecting alight ray on the interior of said screen, and means including fluidpressure sensitive element and a fluid carrying conduit connected tosaid element, for actuating said reflecting member in response to therespiration of a person breathing into said conduit to vary the positionof the light ray on the screen, whereby the respiratory pattern of theperson will be translated into a moving light ray capable of tracing acurve on said rotating screen with said curve continuously observablethrough said viewing scope.

7. A device for continuous observation of a respiratory flow pattern,said device comprising a cylindrical fluorescent screen and means forrotating the screen on its central axis, a viewing scope for observing apart of said screen, a projecting apparatus including a lamp and a lenssystem and a mirror arranged for causing a beam of light to impinge asan intense spot of light of small diameter onto the screen and at theentrance side of the visible part of said screen, whereby to preventmoving light spots from impinging on said visible part of the screen,and a differential pressure device including a fluid carrying conduitconnected thereto and operable by respiration of a person breathing intosaid conduit to actuate said mirror and thereby move said light spot onthe screen, .in a direction at an angle to the direction of movement ofthe screen, whereby the respiratory flow pattern of the person will betranslated into a moving light ray which traces a curve on said visiblepart of the rotating screen continuously observable through said viewingscope.

8. A device for observation of a respiratory flow pattern, said devicecomprising a translucent cylindrical screen and means for slowlyrotating the screen on its central axis, a viewing scope for observingan exterior part of said screen, a projecting apparatus and cooperatingreflecting enemas means to produce alight ray on the interior side ofsaid screen, means including. a fluid pressure sensitive element and afluid carrying conduit image persists for only a, part of the revolution7 of said screen, to equip the screen for continuous excitation, wherebythe respiratory flow pattern of the person will be translated into amoving light, raywhichtraces a curve onthe visible part of; said screen.continuously observable. through saidviewing scope. i V .1 v -WAYLANDREFERENCES CITED The following references file of this patent:

UNITED STATES PATENTS Number Name Date 2,274,182 Asher Feb. 24,1942

t 2,371.;244 Lax Mar, 13, 19 45 are of record in the"

